This area of Yellowstone is geologically unstable and continually changing. I imagine that when those trees were growing, very little or none of the mineral deposits you see in the images existed. Some eruption(s) and/or change(s) in water flow decades ago likely caused acidic and mineralized water to flow into this area, resulting in gradual buildup of layers, dams, and pools as water evaporated and minerals deposited more at the edges. The trees quickly died in the acidic waters and, because decay is very slow in this area, their skeletons hang around for a long time.

Wow I love this Leanne. It really appeals to my sense of scaled repeating patterns. The seagull is an added bonus but a massive fillip to the image. Would love to see this scene with a longer exposure creating the milky effect.

These ducks actually have feathers that retain water so they can dive and swim faster, I read somewhere this species spends 85% of its life under water. Please don't tell me I need to clean my lens or sensor, those are a few thousand flying insects.